<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>select</title>
</head>
<body>
   <div id="main">
       <select name="platform" style="margin-left: 100px">
           <option value="popo">popo</option>
           <option value="plpl">plpl</option>
           <option value="yoyo">yoyo</option>
       </select>
   </div>
</body>
</html>